What does it mean when a guy says 'no anymore' to being with girls?

I like this guy, but he had a girlfriend before who screwed him over three years ago and now he says 'no anymore' to any girls. However, he does like me, he stares at me a lot, gets jealous when I talk to other guys or when I look at them, or even when other guys look at me. He's also shy and introverted. Is he really all that serious when he says 'no anymore' about girls?